It happened to me. I could not reboot my MacBook. It is a newer model with no hard drive, no optical drive, no ethernet port, and a 512 SSD drive. Very fast on the boot up if nothing goes wrong. This piece of hardware is primarily used for work and I do occasionally take work home with me. On this particular occasion I brought the MacBook home with me plugged it in to electrical and ethernet port (thunderbolt to ethernet connector attached) and booted the machine did some work and left for meetings. When I came back the fans were on high there was a spinning black disk. I suspect a problem with the external power supply since a red charging light was on. What to do? Being a mac person I followed standard reboot practices:

• Power off, wait 10 seconds power on – nothing. It would seem to reboot and then freeze.
• Powered off, powered on and pressed the option button to bring me into recovery (there is a hidden recovery partition – usually on sd3). I went into DiskUtility tool and clicked on repair HD (vocabulary hold over). Then clicked on repair permissions. Clicking on repair permissions usually fixes the standard “file folder” question mark problem where the boot block sometimes goes missing. I then rebooted the machine and nothing. It would freeze again on boot up.
• I then did a <command+option+p+r> (press all 4 after you here the beep on powering up again to reset the NVRAM/PRAM. Hold down these 4 keys until it chimes again. Again nothing.
• Then I did a safe boo which involves starting the MacBook and then immediately press the shift key. If you want to see what is going on at any time even during the boot up process hold down the command+v sequence and verbose messages are displayed on the screen as the machine reboots. So to see what was happening during the safe reboot I would press shift+command+v. Safe reboot takes a bit longer since it does a disk check and other operations. From looking at the steps – boot up appeared normal and then it would freeze. I attempted this a few times both safe mode and regular boot and each time the machine would freeze at a different instruction.
• The only option at this point would be a reinstall. The options are to reinstall over the net from Apple, restore from external media, or restore from backup. In each case it would involve erasing the drive and rewriting. I did not have external media (neither DVD nor USB key). From apple would be an option, however in both these cases it would mean a base OS and no other files. My only option was to restore from backup.

So yes, if it can happen to me it can happen to you. I always have connected to my MacBook an external 1Gig USB3 external hard drive that cost $89.00. It was the best investment that was made. I had partitioned in into 2 partitions – a TimeMachine backup and a Work partition (512 SSD is sometimes not enough to hold all your files). I connected the external HD, powered up the MacBook, pressed the option key, and went into recovery mode. Once in recovery I clicked on “recover from TimeMachine backup, clicked on last Friday’s backup and restored my machine. It took 40 minutes to erase and recover. Once done, the MacBook automatically restarted and I was good to go. I am checking logs to see what happened and will replace the power supply at home.

Having an inexpensive backup option saved me. Please if you do not have a backup option get one whether you have a mac, pc or linux device. Trust me when I say:

If it can happen to me, it can happen to you.

-- EdwardChrzanowski - 2014-10-17